Actually, revisionist history is part of the proof. If someone would try to claim something about the past nobody can stop him but there will be many claims to the contrary. Nobody until recent generations questioned the veracity of the Torah’s account. We’ve had many groups of dissenters but none of them argued on the Torah’s account.
After a while it beccomes too late to start neww theories. Nobody can now claim the Civil War didn’t happen. Had someone made such a claim at that time there would be what to discuss. The same goes for holocaust deniers. If they would have found people with their view that had access to know the truth, that would make their claim less ridiculous.